New Directions and Shifting Priorities in HIV Prevention (& some Big Picture Questions for Global Health )

Transcription

1 HARVARD UNIVERSITY SCHOOL OF PUBLIC HEALTH New Directions and Shifting Priorities in HIV Prevention (& some Big Picture Questions for Global Health ) Daniel Halperin, PhD Department of Global Health and Population Harvard University School of Public Health UN General Assembly, October 24, 2008

2 Successes & Failures of AIDS Prevention (focus on sub-saharan Africa) o Epidemiological background: Why is HIV so high in SSA, especially southern Africa? o Evidence for the standard HIV prevention tools? o New approaches and priorities for HIV prevention Th AIDS d i ithi l b l h lth

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4 HIV Prevalence by Region % HIV prevalence Southern Africa Eastern Africa Central Africa West Africa Source: Adapted from WHO analysis (Lancet 2004)

5 HIV Transmission Patterns in Mashonaland, Rural Zimbabwe Wilson and Cowan et al, 2003

6 Concurrent Partnerships Globally Sources: M. Carael, 1995; Halperin and Epstein, L t 2004

7 The Acute Infection Period

8 Source: Kohler H and Helleringer S. The Structure of Sexual Networks and the Spread of HIV in Sub-Saharan Africa: Evidence from Likoma Island (Malawi). PARC Working Paper Series: WPS Sexual Networking in Likoma, Malawi o A fifth of population in exclusive dyadic relationships o Two-thirds linked by single chain of infections over last 3 years o Networks not linked by sex workers or other high frequency transmitters o Linked by decentralized, complex, robust chains of sexual relationships

9 Modeling Sexual Networks Low degree networks create a transmission core Number of Partners Mean: 1.68 Mean: 1.74 Mean: 1.80 Mean: 1.86 Largest components Bicomponents in red In largest component: 2% 10% 41% 64% Source: Martina Morris, University of Washington and James Moody, Duke University, Meeting concurrent sexual partnerships and sexually transmitted infections, Princeton University, 6 May

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11 HIV Prevalence by Male Circ. (Kenya) Source: DHS Kenya 200

12 Physician and health show host Dr Themba Ntiwani, Swaziland: "Everyone wants to have it done. Not one person has called to say it's 'un-swazi" Source: Timberg, Wash Post, Dec. 2005

13 Acceptability of MC in Currently Non- Circumcising Communities in Africa Uganda 1997 Kenya 1999 S Africa Zimbabwe 2000 S Africa 2001 S Africa 2002 Botswana 2003 Swaziland % % of uncircumcised men willing to be circumcised % of women favouring circumcision of their partners Source: Westercamp N, Bailey RC., AIDS Behav., 200

14 Botswana MC Uptake of 80% over 10 Years (Relative Risk = 0.33) 80% 70% 60% 50% 40% 30% 20% 10% 0% Years (MC scale-up at Year 15) Male HIV Prevalence Female Prev. MC Prev. Nagelkerke et al, BMC Inf. Dis. 2007

15 Early successes: Uganda and zero grazing

16 Behavior Change among Males in Manicaland, Zimbabwe yr olds who New sexual partner Casual partner - Condom use - last have started sex - last year LAST MONTH casual partner Source: Gregson et al, 2006

17 % Reporting 2+ Partners in last 12 Months, South African National Surveys

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19 The Standard HIV Prevention Methods - o Condom Promotion: Success stories (e.g., Thailand), in concentrated epidemics driven by commercial sex work, etc. o HIV Testing and Counseling: Important as gateway to treatment/care but little evidence of reducing risky behavior o Treatment of Other Sexually Transmitted Diseases: Also important for public health reasons, yet 7 out of 8 clinical trials found reduced STDs but no impact on HIV o Youth (including Abstinence-based) Programs: Worth promoting delay of debut, use of contraception, etc., but little likelihood of impacting on the overall HIV epidemic

20 ABCs of HIV Prevention

21 Which Model for Southern Africa? o Botswana: A mainly donor-driven, top-down response focusing on clinical service and commodity provision Prioritized condom promotion to general population Supported by strong political leadership o Uganda: Prioritized behavior change (particularly partner reduction) in the general population through a zero-grazing approach, involving churches, traditional leaders & healers, etc. Featured a grassroots, community-based

22 The Difference between Response to AIDS in Botswana, compared to Uganda: Aids had not gone beyond the headspace of awareness, education and counselling to a lower centre of gravity between the gut and the heart of behaviour change. (Daniel Low Beer, 2003)

23 Female-Controlled Method of HIV Prevention?: Uganda in Late 1980s The horror of Slim is forcing people to change social habits. A number of wives openly go so far as to confess that Slim has saved their marriages In Bugolobi, a young housewife with three children, declared with a gleam in her eye, There has been a positive change in our marriage. My husband stays at home much more. And I encourage him to do so by enthusiastically keeping him informed of the latest gossip about Slim victims. (New Vision, October 23, 1987, p.10)

24 Role of Faith Communities in Uganda: o Most people (98%) belong to one of three faith communities: Catholic, Anglican, or Muslim Churches are hierarchical and well organized o Focus group respondents emphasized the role of the church: During Sunday services During/after funerals o Behavioral focus Initially on faithfulness and zero grazing Many later accepted condoms (but mainly emphasized monogamy and abstinence)

25 Under 5 Mortality and Adult HIV Prevalence Under 5 Mortality (Deaths per 1,000 Live Births) Adult HIV Prevalence 2002 Over Less than 129 Over 15% 10% % 3% - 9.9% 1% - 2.9% 0% - 0.9% Source: UNAIDS/WHO; U.S. Census Bureau

26 Contraceptive Prevalence and Adult HIV Prevalence MODERN CONTRACEPTIVE PREVALENCE, MARRIED WOMEN Adult HIV Prevalence % - 4.9% 5% - 9.9% 10% % Over 20% Over 15% 10% % 3% - 9.9% 1% - 2.9% 0% - 0.9% Source: Report on the global HIV/AIDS epidemic. UNAIDS, July 2002; DHS; UN. Hill K, et al. Estimates of maternal mortality for 1995, Bulletin of the World Health Organization 79(3), WHO 2001:

27 Total annual resources available for AIDS

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